Energy and ecosystems

sunlight

By photosynthesis, they use sunlight in producing organic compounds such as glucose

total mass of living material in a specific area at a given time

photosynthetic organisms that manufacture organic substances using light energy, water and carbon dioxide

organisms that obtain their energy by feeding on other consumers rather than using the energy of sunlight directly

Animals

Those that directly eat producers- first in the chain of consumers

Animals that eat primary consumers

Animals that eat secondary consumers

a group of organisms that break down the complex materials in dead organisms into simple ones. In doing so they release valuable minerals and elements in a form that can be absorbed by plants and contribute to recycling

describes a feeding relationship in which the producers are eaten by the primary consumers. These in turn are eaten by secondary consumers and in turn tertiary consumers.

Each stage in a food chain

direction of energy flow

most animals do not rely on a single food source and within a single habitat many food chains will be linked together to form a food web

using dry mass per given area in a given time

a sample of dry material is weighed and is then burnt in pure oxygen within a sealed chamber called a bomb. The bomb is surrounded by a water bath and the heat of combustion

1-3%

-90% of the suns energy is reflected back into space by clouds or absorbed by the atmosphere -not all wavelengths of light can be absorbed and used for photosynthesis -light may not fall on chlorophyll molecule -a factor such as low carbon dioxide levels might affect the rate

The total quantity of the chemical energy store in plant biomass in a given area or volume in given time

20-50%

The chemical energy store that is left when the losses to respiration have been taken into account

plant growth and reproduction

10%

20%